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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?FdbfcWNgvi3Cpja4KF5zyWawRBfcVA/mquFZSoVBfNuu1ucAGWgbDSzmbgCf?= =?us-ascii?Q?ONEeUR9VTWAleg4XdoSjJ5gbpB6PW4umHUqXtcWKb+m0COX5rz1aTsuEGiE3?= =?us-ascii?Q?7sAotpbBh7lRpGjEA+2YcFvYLDQ3U+ND1v/5B1p+uSY/oduImbn0rbrNgQ0x?= =?us-ascii?Q?PZCN5ZdAxKrOdsfUSuZyaorVPWrSUx73xA+zO/XMtm5cbzZtdLCNMfowH1u2?= =?us-ascii?Q?Q/3/suRuyeUoeip+GkFhbg7R0F8T8hziGGqLpWuaD9vqwkTF1hU096D1IXHD?= =?us-ascii?Q?nkPujiPq5eRuUynlhVMDvD/tEiL/pjJO/+FWloa+WLiTgg2vtTYg8hJEy1RR?= =?us-ascii?Q?r1yjc429jPq72N+hI70UeNLx1zRDDmTKAzfRm682YLcjPyk1wOM3qTMJAuA1?= =?us-ascii?Q?MubomLrWY2kxq0AJ+AxhWskC+y1t76VOcP9LHrdw/V2qeIJmeivq5M6AZRpn?= =?us-ascii?Q?5eR0WyewlZ4zyi+//L29uKFClJ03b6paUrRIbh8M1OGioKto57wc1cf/yH/L?= =?us-ascii?Q?UGoQTQalYNrBhEL7bxjtkLI0ZzPEsSE+Tsyc7oXteWQJyizMTDvNhDB83D54?= =?us-ascii?Q?LF1bGRW2oCNVtOu7BrdsoE3NyLpBnidWh8zAYJKf1OOie/fX58QE+F4nVd2I?= =?us-ascii?Q?9BGn35KpYxJwbGCM2zf5ITRkmXCQD0pzZWoVxvqMYoJN+mMTMmRTPAUeCmVj?= =?us-ascii?Q?ZIfVV5ViVWWJFyCnozcqM48Jw+XEzipvStiINt/UfnE9KO2nt36oNYkQuskW?= =?us-ascii?Q?7AZeK6zyPXuz2K4VsDSggVQEUs6OQzriq8+12Q1SRhVyA2zr/BcOhOGFQrvR?= =?us-ascii?Q?2RzkA+g/tG1tGbDOmIN5p/1xb4kbDUbRclUrQjJJq3X3Z3YrH5rmSRVcbYSj?= =?us-ascii?Q?Q0IPll4qdd7rcFpXBkFtXDzeQJbti+idoRariK2+ZOmRZ6uXCduDqZ+i7Zo9?= =?us-ascii?Q?fYAkQk6IKXkS5dWD7nni2eSx+5s+q+sp4cSj2tq0efXU/ErAxi/hKomQ1FzE?= =?us-ascii?Q?rsv2UEfw315d+t3R/yGg6+IQPAnMTIv9Nn1b/aAallo+NAewxPDyX2KSgx50?= =?us-ascii?Q?DXw/cWHIdHo36I87n9Ng2Yv61XRQGRCGU6U9NJCPqSB8UraZud0oN9drup0v?= =?us-ascii?Q?PsL59BnSwHk8cdQAkfMfymZyNHsxvE2DIklOX7yl/OFX9IN5f1dNFZUcrwrT?= =?us-ascii?Q?m55Dyc53Fx8UCUXDFu2tqzOMqwd7Cj3Hfzw5m9wZRCayE87g0TTZK+/SVLVb?= =?us-ascii?Q?Q0LU87XAGRoPiOUa2NMNSZS11URulL8SsefuKkxs2yA32+hhny/uGLPXf05R?= =?us-ascii?Q?+h5viDfA63Un7b/Dle+BwB5nqpi9vXzhGQReTl/JHuIJKQkDHVbACgtZK+N9?= =?us-ascii?Q?LIxhNSSX3m0JnMbETY4Rcfhc0CYZ6+VcvZ9ZukZlrLmpNTvoGirByvqr1UJK?= =?us-ascii?Q?VwURgZBE4QHG6qF5KKdvGm3cRZ8us1rqVqan73ulpGgiEgeNTjOBKP8OcKly?= =?us-ascii?Q?hv419p/3N9s/yW3u+AUIwZ0BCdKRvANgRBiO+Fj/VppDq3vBgP9A3xc9sOlh?= =?us-ascii?Q?Jr0PCOZxuBAbIyH0NyqSP0TsOCUrSY7+DXyyMqLXIGpRj6nEckYhvOWZUMLn?= =?us-ascii?Q?uQO/h3xsKh3s2nNOzl1ll+4omNU53NIz/J+kQ5qTcONLhG2Gt7uU/j+yTfkT?= =?us-ascii?Q?fiMoXqQD5UOSrq8BJvZYDnQqqZrNRToeMMHqmiCjqsrt9MNqo/cX3g9GLtqY?= =?us-ascii?Q?ONYIaCoMEg=3D=3D?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2996d7e0-d60b-46df-ee83-08da38bb55fe X-MS-Exchange-CrossTenant-AuthSource: VE1PR04MB6560.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 May 2022 10:44:08.0563 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: eoKnvp7VNOnz2/UY0e3z8eZg+sBrsbqieCH9Gh8LH0qjExlNmeoLIpCvw2AkC4XyTiHQFJnbR0j8ZaInLhPzkQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR04MB8386 On 11.05.2022 13:08, Roger Pau Monn=C3=A9 wrote: > On Mon, Apr 25, 2022 at 10:43:45AM +0200, Jan Beulich wrote: >> When a page table ends up with all contiguous entries (including all >> identical attributes), it can be replaced by a superpage entry at the >> next higher level. The page table itself can then be scheduled for >> freeing. >> >> The adjustment to LEVEL_MASK is merely to avoid leaving a latent trap >> for whenever we (and obviously hardware) start supporting 512G mappings. >> >> Signed-off-by: Jan Beulich >> Reviewed-by: Kevin Tian >=20 > Like on the AMD side, I wonder whether you can get away with only FTAOD I take it you mean "like on the all-empty side", as on AMD we don't need to do any cache flushing? > doing a cache flush for the last (highest level) PTE, as the lower > ones won't be reachable anyway, as the page-table is freed. But that freeing will happen only later, with a TLB flush in between. Until then we would better make sure the IOMMU sees what was written, even if it reading a stale value _should_ be benign. Jan > Then the flush could be done outside of the locked region. >=20 > The rest LGTM. >=20 > Thanks, Roger. >=20